Vehicle recharge of home energy storage

ABSTRACT

A method for managing energy for a building includes connecting a power line of the building to a battery of a vehicle via a charger; responsive to occurrence of a power outage, supplying electric energy to the building from the battery and from an energy storage separate from the vehicle; and instructing the vehicle to recharge the battery and return to the building at a predefined time before stored energy of the energy storage falls below a predefined value.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.17/018,213, filed Sep. 11, 2020, the disclosure of which is herebyincorporated in its entirety by reference herein.

TECHNICAL FIELD

The present disclosure relates to a home energy management systemcoordinated with an electric vehicle.

BACKGROUND

A home energy ecosystem (HEE) may include various components such ashome energy storage (HES), electric vehicle, appliance, thermostat,solar panel and other devices operated and controlled via a home energymanagement system (HEMS). The HEMS may coordinate various components ofthe ecosystem to enhance convenience, increase efficiency and reduceenergy cost. In case of a power outage (e.g. utility service upgrade),the HEMS may use energy stored in the HES to temporarily provideelectric power to a household. However, due to the limited capacity ofthe HES, the HEMS may be unable to continuously power the householduntil the power restores.

SUMMARY

In one or more illustrative embodiments of the present disclosure, asystem for managing energy of a building includes a controller incommunication with a charger and configured to responsive to predicting(i) a coming power outage of an expected duration and (ii) a totalenergy reserve of a battery of a vehicle and an electric energy storagebeing less than an anticipated amount of energy to be used by thebuilding during the expected duration, instruct the vehicle to rechargethe battery at a target charge station and return before stored energyof the energy storage falls below a predefined value, and responsive toencountering the power outage, command the charger to supply electricenergy to the building from the battery and electric energy storage.

In one or more illustrative embodiments of the present disclosure, amethod for managing energy for a building includes connecting a powerline of the building to a battery of a vehicle via a charger; responsiveto occurrence of a power outage, supplying electric energy to thebuilding from the battery and from an energy storage separate from thevehicle; and instructing the vehicle to recharge the battery and returnto the building at a predefined time before stored energy of the energystorage falls below a predefined value.

In one or more illustrative embodiments of the present disclosure, anenergy management system for a building includes a controller incommunication with one or more electric consuming devices, an electricenergy storage, and a charger configured to connect to an electricvehicle having a battery, wherein the controller is configured to,responsive to detecting a power outage and an energy reserve of thebattery and energy storage being less than a predefined threshold,suspend power supply to the electric consuming devices classified asnon-essential and continue to supply power to the electric consumingdevices classified as essential.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of an electrified vehicle illustrating drivetrainand energy storage components including an electric machine.

FIG. 2 is a diagram of a HEMS associated with an electric vehicle.

FIG. 3 is a flow diagram for a process of the HEMS.

FIG. 4 is a flow diagram for another process of the HEMS.

FIGS. 5A and 5B are waveform diagram of the HES and vehicle batterystate of charge.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described herein. It is to beunderstood, however, that the disclosed embodiments are merely examplesand other embodiments can take various and alternative forms. Thefigures are not necessarily to scale; some features could be exaggeratedor minimized to show details of particular components. Therefore,specific structural and functional details disclosed herein are not tobe interpreted as limiting, but merely as a representative basis forteaching one skilled in the art to variously employ the presentinvention. As those of ordinary skill in the art will understand,various features illustrated and described with reference to any one ofthe figures can be combined with features illustrated in one or moreother figures to produce embodiments that are not explicitly illustratedor described. The combinations of features illustrated providerepresentative embodiments for typical applications. Variouscombinations and modifications of the features consistent with theteachings of this disclosure, however, could be desired for particularapplications or implementations.

FIG. 1 depicts an electrified vehicle 112 that may be referred to as aplug-in hybrid-electric vehicle (PHEV). A plug-in hybrid-electricvehicle 112 may comprise one or more electric machines 114 mechanicallycoupled to a hybrid transmission 116. The electric machines 114 may becapable of operating as a motor or a generator. In addition, the hybridtransmission 116 is mechanically coupled to an engine 118. The hybridtransmission 116 is also mechanically coupled to a drive shaft 120 thatis mechanically coupled to the wheels 122. The electric machines 114 canprovide propulsion and braking capability when the engine 118 is turnedon or off. The electric machines 114 may also act as generators and canprovide fuel economy benefits by recovering energy that would normallybe lost as heat in a friction braking system. The electric machines 114may also reduce vehicle emissions by allowing the engine 118 to operateat more efficient speeds and allowing the hybrid-electric vehicle 112 tobe operated in electric mode with the engine 118 off under certainconditions. An electrified vehicle 112 may also be a Battery ElectricVehicle (BEV). In a BEV configuration, the engine 118 may not bepresent.

A traction battery or battery pack 124 stores energy that can be used bythe electric machines 114. The vehicle battery pack 124 may provide ahigh voltage direct current (DC) output. The traction battery 124 may beelectrically coupled to one or more power electronics modules 126 (suchas a traction inverter). One or more contactors 142 may isolate thetraction battery 124 from other components when opened and connect thetraction battery 124 to other components when closed. The powerelectronics module 126 is also electrically coupled to the electricmachines 114 and provides the ability to bi-directionally transferenergy between the traction battery 124 and the electric machines 114.For example, a traction battery 124 may provide a DC voltage while theelectric machines 114 may operate with a three-phase alternating current(AC) to function. The power electronics module 126 may convert the DCvoltage to a three-phase AC current to operate the electric machines114. In a regenerative mode, the power electronics module 126 mayconvert the three-phase AC current from the electric machines 114 actingas generators to the DC voltage compatible with the traction battery124.

The vehicle 112 may include a variable-voltage converter (VVC) (notshown) electrically coupled between the traction battery 124 and thepower electronics module 126. The VVC may be a DC/DC boost converterconfigured to increase or boost the voltage provided by the tractionbattery 124. By increasing the voltage, current requirements may bedecreased leading to a reduction in wiring size for the powerelectronics module 126 and the electric machines 114. Further, theelectric machines 114 may be operated with better efficiency and lowerlosses.

In addition to providing energy for propulsion, the traction battery 124may provide energy for other vehicle electrical systems. The vehicle 112may include a DC/DC converter module 128 that converts the high voltageDC output of the traction battery 124 to a low voltage DC supply that iscompatible with low-voltage vehicle loads. An output of the DC/DCconverter module 128 may be electrically coupled to an auxiliary battery130 (e.g., 12V battery) for charging the auxiliary battery 130. Thelow-voltage systems may be electrically coupled to the auxiliary battery130. One or more electrical loads 146 may be coupled to the high-voltagebus/rail. The electrical loads 146 may have an associated controllerthat operates and controls the electrical loads 146 when appropriate.Examples of electrical loads 146 may be a fan, an electric heatingelement and/or an air-conditioning compressor.

The electrified vehicle 112 may be configured to recharge the tractionbattery 124 from an external power source 136. The external power source136 may be a connection to an electrical outlet. The external powersource 136 may be electrically coupled to a charger or electric vehiclesupply equipment (EVSE) 138. The external power source 136 may be anelectrical power distribution network or grid as provided by an electricutility company. The EVSE 138 may provide circuitry and controls toregulate and manage the transfer of energy between the power source 136and the vehicle 112. The external power source 136 may provide DC or ACelectric power to the EVSE 138. The EVSE 138 may have a charge connector140 for plugging into a charge port 134 of the vehicle 112. The chargeport 134 may be any type of port configured to transfer power from theEVSE 138 to the vehicle 112. The charge port 134 may be electricallycoupled to a charger or on-board power conversion module 132. The powerconversion module 132 may condition the power supplied from the EVSE 138to provide the proper voltage and current levels to the traction battery124. The power conversion module 132 may interface with the EVSE 138 tocoordinate the delivery of power to the vehicle 112. The EVSE connector140 may have pins that mate with corresponding recesses of the chargeport 134. Alternatively, various components described as beingelectrically coupled or connected may transfer power using a wirelessinductive coupling. Additionally, the vehicle 112 may be configured toprovide electric power from the traction battery 124 to off-board powerstorage (not shown) via the EVSE 138 and EVSE connection 140 under thecontrol of controllers such as the power conversion module 132.Alternatively, the power transfer from the traction battery 124 to theoff-board load (e.g. the HES) may be performed without utilizing thepower conversion module 132 since both the traction battery 124 and theHES are DC power. The traction battery 124 may be directly connected tothe charge port to transfer and/or receive DC power. For instance, theEVSE 138 may be integrated or associated with a home having a HES aspower backup. The vehicle 112 may be operated as a portable powerstorage to transfer power from and to the HES coordinated by a HEMS (tobe described in detail below).

One or more wheel brakes 144 may be provided for braking the vehicle 112and preventing motion of the vehicle 112. The wheel brakes 144 may behydraulically actuated, electrically actuated, or some combinationthereof. The wheel brakes 144 may be a part of a brake system 150. Thebrake system 150 may include other components to operate the wheelbrakes 144. For simplicity, the figure depicts a single connectionbetween the brake system 150 and one of the wheel brakes 144. Aconnection between the brake system 150 and the other wheel brakes 144is implied. The brake system 150 may include a controller to monitor andcoordinate the brake system 150. The brake system 150 may monitor thebrake components and control the wheel brakes 144 for slowing thevehicle. The brake system 150 may respond to driver commands and mayalso operate autonomously to implement features such as stabilitycontrol. The controller of the brake system 150 may implement a methodof applying a requested brake force when requested by another controlleror sub-function.

Electronic modules in the vehicle 112 may communicate via one or morevehicle networks. The vehicle network may include a plurality ofchannels for communication. One channel of the vehicle network may be aserial bus such as a Controller Area Network (CAN). One of the channelsof the vehicle network may include an Ethernet network defined byInstitute of Electrical and Electronics Engineers (IEEE) 802 family ofstandards. Additional channels of the vehicle network may includediscrete connections between modules and may include power signals fromthe auxiliary battery 130. Different signals may be transferred overdifferent channels of the vehicle network. For example, video signalsmay be transferred over a high-speed channel (e.g., Ethernet) whilecontrol signals may be transferred over CAN or discrete signals. Thevehicle network may include any hardware and software components thataid in transferring signals and data between modules. The vehiclenetwork is not shown in FIG. 1 but it may be implied that the vehiclenetwork may connect to any electronic module that is present in thevehicle 112. A vehicle system controller (VSC) 148 may be present tocoordinate the operation of the various components.

FIG. 2 depicts a diagram of a home energy management system associatedwith an electric vehicle. The HEE 200 in the present example may beimplemented for a house 202. The house 202 may access electric powerfrom a power grid 204 via a switch board 206 configured to providevarious components of the HEE 200 with electric power via an internalpowerline 234. For instance, the HEE 200 may include one or moreelectric equipment 210 (e.g. appliance) configured to consumeelectricity and provide various features to the household. The HEE 200may further include a HES 208 configured to store electric energy. TheHES 208 may be implemented in various forms. As an example, the HES 208may include a rechargeable battery (e.g. lithium-ion battery) to storeelectric energy received from the grid 204 and to provide the electricenergy to the internal powerline 234 whenever needed. Since the electricenergy may be stored as DC power in the HES 208, one or more DC/ACinverters may be provided with the HES 208 for power transitions.

With continuing reference to FIG. 1 , the internal powerline 234 may befurther connected to an EVSE 138 configured to transfer electric energywith an electric vehicle 112. The EVSE 138 may be installed within ornear the house 202 (e.g. in a garage) and adapted to a home electricenergy configuration having a predefined voltage and maximum currentsupported by the switch board 206. As discussed with reference to FIG. 1, the EVSE 138 may be configured to connect to the vehicle 112 via thecharge port 134 to charge the traction battery 124. Additionally, theEVSE 138 may be further configured to draw electric power from thetraction battery 124 of the vehicle 112 to supply power to the HEE 200.For instance, in case of a power outage from the grid 204, the EVSE 138may be configured to draw electric power from the vehicle 112 to powerthe components of the house 202. The power management of the HEE 200 maybe controlled and coordinated by a HEMS controller 212 associated withhouse 202. The HEMS controller 212 may be implemented in variousmanners. For instance, the HEMS controller 212 may be a dedicatedcontroller located within the house 202 and connected to components ofthe home energy ecosystem or smart home devices HEE 200 via wired orwireless connections (not shown). Alternatively, the HEMS controller 212may be implemented by a desktop or laptop computer configured to runprocesses and programs to perform the controller operations.Alternatively, the HEMS controller 212 may be integrated with one ormore components of the home energy ecosystem HEE 200 such as the EVSE138. Alternatively, the HEMS controller 212 may be remotely implementedvia a cloud server through the Internet and configured to monitor andcontrol the operations of components of the home energy ecosystem HEE200. In any or all of the above implementation examples, the HEMScontroller 212 may be provided with software to monitor and control theoperations of the various components of the home energy ecosystem HEE200. The HEMS controller 212 may be further provided with an interfaceassociated with input and output devices to interact with a user of theHEE 200. The HEMS 212 may be further connected to a cloud 232 via apublic or private network to communicate with other entities such as theutility company and weather agencies to facilitate the planning andcontrolling of the HEE 200.

With continuing reference to FIG. 1 , the vehicle 112 may furtherinclude various components to facilitate the power transaction betweenthe battery 124 and the EVSE 138. The vehicle 112 may include a systemcontroller 148 configured to perform instructions, commands and otherroutines in support of the processes described herein. For instance, thesystem controller 148 may include one or more processors and beconfigured to execute instructions of vehicle application 228 to providefeatures such as wireless communication and power management. Suchinstructions and other data may be maintained in a non-volatile mannerusing a variety of computer-readable storage medium 226. Thecomputer-readable medium 226 (also referred to as a processor-readablemedium or storage) may include any non-transitory medium (e.g. tangiblemedium) that participates in providing instructions or other data thatmay be used by the system controller 148. Computer-executableinstructions may be compiled or interpreted from computer programscreated using a variety of programming languages and/or technologies,including, without limitation, and either alone or in combination, Java,C, C++, C#, Objective C, Fortran, Pascal, Java Script, Python, Perl, andPL/SQL.

The vehicle 112 may further provided with navigation and route planningfeatures through a navigation controller 224 configured to calculatenavigation routes responsive to user input via e.g. HMI controls (notshown) and output planned routes and instructions via an output devicesuch as a speaker or a display (not shown). Location data that is neededfor navigation may be collected from a global navigation satellitesystem (GNSS) controller 216 configured to communicate with multiplesatellites and calculate the location of the vehicle 112. The GNSScontroller 216 may be configured to support various current and/orfuture global or regional location systems such as global positioningsystem (GPS), Galileo, Beidou, Global Navigation Satellite System(GLONASS) and the like. Map data used for route planning may be storedin the storage 226 as a part of the vehicle data 230. Navigationsoftware may be stored in the storage 226 as a part of the vehicleapplications 228.

The vehicle 112 may be further configured to wirelessly communicate witha variety of digital entities via a wireless transceiver 214. Forinstance, the vehicle 112 may be configured to communicate with the HEMScontroller 212 via the wireless transceiver 214 to perform variousoperations. Additionally or alternatively, the communication between thevehicle 112 and the HEMS controller may be enabled by the EVSE connector140 coupled with the charge port 134 configured to support digitalcommunication protocols. The wireless transceiver may be configured tosupport a variety of wireless communication protocols enabled bywireless controllers (not shown) in communication with the wirelesstransceiver 214. As a few non-limiting examples, the wirelesscontrollers may include a Wi-Fi controller, a Bluetooth controller, aradio-frequency identification (RFID) controller, a near-fieldcommunication (NFC) controller, and other devices such as a Zigbeetransceiver, an IrDA transceiver, an ultra-wide band (UWB) transceiver,or the like.

The vehicle 112 may be further provided with a telematics control unit(TCU) 218 configured to control telecommunication between the vehicle112 and the cloud 232 through a wireless connection 236 using a modem220. The wireless connection 236 may be in the form of variouscommunication network e.g. cellular network. Through the wirelessconnection 236, the vehicle 112 may access one or more servers of thecloud 232 to access various content for various purposes. The vehicle112 may be further provided with autonomous driving features via anautonomous driving controller (ADC) 222. The ADC 222 may be configuredto perform autonomous driving for the vehicle 112 in conjunction withthe navigation controller 224 using map data stored in the storage 226and live data from the cloud 232. It is noted that the term cloud isused as a general term in the present disclosure and may include anycomputing network involving carriers, router, computers, servers, or thelike configured to store data and perform data processing functions andfacilitate communication between various entities.

The various components of the vehicle 112 introduced above may beconnected to each other via in-vehicle network 238. The in-vehiclenetwork 238 may include, but is not limited to, one or more of acontroller area network (CAN), an Ethernet network, and a media-orientedsystem transport (MOST), as some examples.

Referring to FIG. 3 , an example flow diagram for a process 300 of theHEMS is illustrated. With continuing reference to FIGS. 1 and 2 , theprocess 300 may be implemented via the HEMS controller 212 of the homeenergy ecosystem HEE 200. At operation 302, the HEMS controller 212collects data related to an anticipated (e.g. scheduled or predicted)power outage from the grid 204. The data relevant to the anticipatedpower outage may be predefined by the system. As a few non-limitingexamples, data relevant to the power outage may include weather forecastreceived from the cloud 232, utility planned maintenance received fromthe cloud 232, user input via the interface of the HMI controller 212,season of the year, current and predicted electrical loads on local andregional distribution and transmission system received from the cloud232, and government announcements received from the cloud 232. With thedata received, the HEMS controller 212 may determine any scheduledoutage. Additionally, the HEMS controller 212 may analyze the data topredict a power outage. For instance, HEMS controller 212 may calculatean outage probability based on weather forecast or electrical loads andcompare the probability with a predetermined threshold (e.g. 50%) topredict if an outage is likely. At operation 304, if the HEMS controller212 determines no outage is likely to happen, the process proceeds tooperation 306 and the HEMS controller 212 keeps a current power planunchanged and may continue to use energy from the HES 208.

Otherwise, if the HEMS controller 212 determines a scheduled orpredicted power outage is likely, the process proceeds to operation 308and the HEMS controller 212 calculates how much energy reservation isneeded based on the length of the outage and power consumption of thehome 202. For instance, the HEMS controller 212 may obtain the length ofoutage based on a planned maintenance schedule (e.g. one hour).Alternatively, the HEMS controller 212 may predict the length of thepower outage using the data received at previous operations. Since theprediction depends on various moving factors, the predicted duration maybe less accurate compared with the outage schedule from the utilitycompany or government. However, a duration prediction may still beuseful to provide an approximate estimation for backup power supplyplanning in advance. The HEMS controller 212 may obtain the powerconsumption by evaluating a power rating of the electric equipment 210and a present power output at the switch board 206. For instance, theHEMS controller may communicate with one or more electric equipment 210to determine their average or current power consumption via wired orwireless connections. Alternatively, HEMS controller 212 may beconfigured to determine a power plan for backup supply mode to implementduring the power outage to reduce and limit certain unnecessary poweroutput. For instance, during a power outage, the HEMS controller 212 mayuse backup/reserved energy from the HES 208 to supply the home 202. TheHEMS controller 212 may suspend power output to the EVSE 138 and/or somepredefined non-essential electric equipment 210 to prolong the time ofbackup supply. Based on the scheduled/predicted outage length, the HEMS212 may dynamically adjust the backup power plan to decide to continueor suspend power supply to the electric power equipment. For instance,for a short power outage anticipated, the HEMS controller may beconfigured to only suspend power supply to the EVSE 138 while continuingto supply power from the HES 208 to all other equipment 210 of the home202 as normal. With an increased length of the power outage, the HEMScontroller 212 may decide to suspend power supply to other predefinedequipment 210 classified as non-essential such as game console, musicplayer, garden light or the like.

Additionally, at operation 310, the HEMS controller 212 calculates apower reserve threshold for the HES 208 based on the backup power supplyplan in anticipation for the power outage. For instance, the HES reservethreshold may be set to 30% in a normal condition without theanticipated power outage. Responsive to the anticipated power outage,the HEMS controller 212 may calculate and increase the HES reservethreshold to 90%. There may be various reasons for a low initial HESreserve threshold. As an example, the utility company providingelectricity may apply flexible pricing for the area covering the house202. The rate may be high during normal hours (e.g. 7 AM to 11 PM) andlow during afterhours (e.g. 11 PM to 7 AM). The HEMS controller 212 mayrecharge the HES 208 during afterhours when the rate is low and use theHES 208 to supply power to the HEE 200 during normal hours to save cost.At operation 312, the HEMS controller 212 implements the new thresholdas calculated to the HES 208. At operation 314, responsive toencountering the power outage as anticipated, the HEMS controller 212implements the backup power supply plan determined at operation 308 tosupply electric power from the HES 208 to essential equipment 210 (suchas sump pump, appliance, telephone, internet router or the like) of theHEE 200.

As an alternative example, the process 300 illustrated in FIG. 3 may besimplified and applied to a situation in which the power outage is notanticipatable. For instance, the power outage may occur without anyprior notice. Responsive to the outage, The HEMS controller 212 mayswitch to the backup mode and supply power to the HEE 200 from the HES208 and/or the vehicle 112. The HEMS controller 212 may prioritize touse the traction battery 124 first to leave sufficient power storage inthe HES 208. Responsive to the total energy storage of both the HES 208and the traction battery 124 dropping below a predefined threshold andthe power outage continuing, the HEMS 212 may instruct the vehicle 112to recharge the traction battery 124 and return to the house 202 beforethe HES 208 runs out. In case that the vehicle 112 is provided withautonomous driving features, autonomous driving instructions may beprovided. The HMS controller 212 may repeat the process until the poweris restored.

Referring to FIG. 4 , a flow diagram for a process 400 of the HEMS ofanother embodiment of the present disclosure is illustrated. Differentfrom the process 300 illustrated with reference to FIG. 3 , in thepresent example, the electric vehicle 112 is involved in the backuppower planning. With continuing reference to FIGS. 1 to 3 , the process400 described herein may be implemented via the HEMS controller 212individually, or in conjunction with the system controller 148.Alternatively, the system controller 148 of the vehicle 112 may beconfigured to perform any or all of operations of the process 400. Forsimplicity, the following description will be made with reference to theHEMS controller 212 alone. At operation 402, the HEMS controller 212collects data relevant to the power outage similar to the operationperformed at 302. At operation 404, the HEMS controller 212 determinesif a power outage has occurred or is anticipated. If the answer is no,the process returns to operation 402. If the answer is yes, the processproceeds to operation 406 and the HEMS controller 212 estimates theamount of energy needed during the outage and determines the backuppower supply plan which is similar to the operation performed atoperation 308 of the process 300. At operation 408, the HEMS controller212 estimates an available energy that can be transferred from thevehicle to the HES 208 via the EVSE 138. The available amount of energyfrom the vehicle 112 may be estimated via the current state of charge(SOC), and/or the amount of energy of the traction battery 124. In casethe vehicle is being used when the estimation is performed, the HEMScontroller 212 may calculate an estimated SOC upon arriving at the houseusing a current location and route of the vehicle 112 received from thecloud 232 and calculate the available energy using the estimated SOC orenergy amount to provide an approximate estimation. At operation 410,the HEMS controller 212 calculates the amount of energy that the HES 208is able to store to provide the backup power supply during the outage.In case the HES 208 is not fully charged, at operation 412, the HEMScontroller 212 coordinates an energy transfer from the traction battery124 to the HES 208 via the EVSE 138.

At operation 414, the HEMS controller 212 determines if the energystored in both the HES 208 and the vehicle battery 124 is enough to lastthrough the duration of the power outage as anticipated. If the answeris yes, the process proceeds to operation 418 and the HEMS controller212 operates the HES 208 to provide backup power supply to the HEE 200during the outage implementing the backup power plan calculated atoperation 406. However, if the answer at operation 414 is no, theprocess proceeds to operation 416. The HEMS controller 212 notifies thevehicle user about the insufficient battery charge and instructs theuser to recharge the vehicle and return to the house 202 before the HES208 runs out as calculated. The instructions provided by the HEMScontroller 212 may include a location of the charging station that isnot affected by the power outage. The instructions may further include atime to start to drive to the charging station calculated to optimizethe backup power plan. In case the target charging station acceptsreservation, the HEMS controller 212 may further place a reservationwith the target charging station at an estimated time of arrival tomaximize the chance that the vehicle 112 can be charged in time. In casethat the vehicle 112 is provided with autonomous driving features, theinstructions may further include driving instructions for the ADC 222 todirect the vehicle 112 to drive to the target charging stationautonomously. If the vehicle 112 is not currently at home and thebattery 124 has capacity to accommodate more charges, the HEMScontroller 212 may instruction the vehicle 112 to stop by the targetcharging station before coming home.

Referring to FIGS. 5A and 5B, SOC waveform diagrams for the HES 208 andvehicle battery 124 of embodiments of the present disclosure areillustrated. With continuing reference to FIGS. 1 to 4 , FIG. 5Aillustrates waveform diagrams for an embodiment that the vehicle batteryis sufficient and does not need a recharge during the backup power mode(“Yes” for operation 414 of FIG. 4 ), whereas FIG. 5B illustrateswaveform diagrams for an embodiment that the vehicle 112 drives to thetarget charging station and is recharged during the backup power mode(“No” for operation 414 of FIG. 4 ). Referring to FIG. 5A, the HES 208starts to discharge responsive to encountering the power outage a time0. As illustrated by way of the waveform 502, during the discharges theSOC of the HES 208 reduces from 90% at time 0 to 30% at time 10 hourswhen the vehicle 112 starts to recharge the HES 208 to 90% SOC under thecontrol of the HEMS controller 212 (and/or the system controller 148 ofthe vehicle 112). As illustrated in the corresponding waveform 504 forthe vehicle battery 124, the SOC of the battery 124 maintains at 80%from time 0 to 10 hours during which no power is drawn from the battery124. At around the 10 hour time point, the vehicle battery 124 starts tosupply power to charge the HES 208 and reduces to approximately 70%after the first vehicle battery discharge completes. The HES/vehiclebattery charge/discharge process repeats according to the backup powerplan calculated by the HEMS controller 212 until the power supply fromthe grid 204 resumes.

FIG. 5B illustrates an alternative HES/vehicle battery power supplyprocess. In this example, the HEMS controller 212 determines the SOC ofthe HES 208 and vehicle battery 124 may be insufficient to last throughthe power outage and command the vehicle 112 to recharge the battery 124to provide further supply to the HEMS power backup. The waveform 506 forthe HES 208 is generally the same as in FIG. 5A. However, responsive tothe vehicle battery 124 reducing to 20% SOC after the first discharge,the vehicle is driven to the target charging station for a recharge asplanned. As illustrated in waveform 508, the SOC of the vehicle battery124 increases from 20% to approximately 90% during the recharge and thevehicle 112 returns to the house 202 for a second discharge to continueto supply power to the HEE 200.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A method for managing energy for a building,comprising: connecting a power line of the building to a battery of avehicle via a charger; responsive to occurrence of a power outage,supplying electric energy to the building from the battery and from anenergy storage separate from the vehicle; and instructing the vehicle torecharge the battery and return to the building at a predefined timebefore stored energy of the energy storage falls below a predefinedvalue.
 2. The method of claim 1, further comprising: predicting thepower outage and a corresponding duration using data from a cloudserver; monitoring power consumption of one or more devices of thebuilding; calculating an amount of energy needed for the building forthe corresponding duration based on the power consumption; and comparingthe amount with a total available energy reserve determined usingavailable energy of both the battery and energy storage.
 3. The methodof claim 2, further comprising responsive to detecting the vehicle isaway from the building, calculating the available energy of the batterybased on a current amount of energy stored by the battery and a plannedroute for the vehicle to drive to the building.
 4. The method of claim1, further comprising providing instructions to the vehicle to permitthe vehicle to autonomously drive to and from a target charging stationfor the recharge.
 5. The method of claim 4, further comprising placing areservation at the target charging station.
 6. The method of claim 1,further comprising responsive to occurrence of the power outage,suspending power supply to consumers classified as non-essential andcontinuing power supply to consumers classified as essential.